When to use public and private voting?

I'm never sure when I make a poll if I should set it to public or private voting. Should it just be at your own discretion, or are there times when one should be preferable to the other? What do you do and why?

It really depends on what the topic's about. If it's about really personal and private things, then private voting is preferred; if the poll is asking people what toy, food, etc. they like, then you can choose public voting. Here's an older thread about the subject.

Most of the time I like public voting. I think it is a fun way to get to know each other. But there are times when I choose not to answer a public voting poll because I consider the information private. I decide on public vs private by deciding what I care about the most. If I just want the information I make it private. If I care more about know what people are thinking and who is it that thinks what, I choose public.